Pig production has high energy consumption thus the energy efficiency of a building is very important. The objective of this paper is a qualitative and quantitative evaluation of thermal properties and thermal bridges in the structure of a newly constructed piggery. The results prove unsuitable thermal properties of the majority of structures. Characteristic thermal properties: external walls (UT=0.470 W∙m-2∙K-1), flooring (UT=1.356 W∙m-2∙K-1), ceiling (UT=0.229 W∙m-2∙K-1), windows and doors (UT=1.70 W∙m-2∙K-1). Qualitative detection of thermal defects with utilization of infrared thermography claimed the most significant thermal bridges on uninsulated socle and flooring, steel concrete straining band of the wall, bearing steel roof frames and window and door frames. The energy efficiency of buildings is significantly affected by the built structure properties and some structures of the measured buildings had low thermal insulation and caused high heat losses.